The new technology was something called "neutron activation." It could solve crimes through microscopic analysis of bits of hair, according to the lecturer at the State Police Academy in Sea Girt.

Sgt. Sam Guzzi scribbled notes as fast as he could guide his pen across the paper.

A human hair had been found a couple of years earlier on a hammer in the car of Linden resident Robert Zarinsky. A police chemist determined it did not belong to Rosemary Calandriello, the 17-year-old girl from Guzzi's town who had vanished in the summer of 1969 on the way to the store for milk.

Now the hair lay inside the Atlantic Highlands police headquarters, sealed in a brown evidence envelope. It was Nov. 17, 1971. Guzzi had labored mightily to prove Zarinsky killed Rosemary. While the circumstantial case was powerful, Guzzi was finally convinced that, without Rosemary's body, the case would never go to court.

But if the encouraging new science could tie Zarinsky to another case, one in which a body had been found . . .

Back in his office, Guzzi telephoned the prosecutor's office in neighboring Middlesex County, where the body of 17-year-old Linda Balabanow had been discovered in the Raritan River. She had been brutally killed five months before Rosemary's disappearance.

"Do you have a sample of Linda Balabanow's hair?" Guzzi asked the detective who took his call. "Can you get one?"

That was almost three years ago, the detective said.

"Please," Guzzi insisted. "Try."

BASTION OF GRIEF

Life all but stopped for the Balabanow family when Linda died. Her grief-stricken parents, Paul and Peggy, did little else but reflect on their loss.

A detective went to their home to retrieve a hair sample and found that, two years and eight months after Linda's death, her bedroom still looked as if she were expected home at any moment. Her clothes hung neatly in the closet, and her guitar stood in the corner. Her hairbrush lay on top of the dresser -- right where she set it down on the last morning of her life. Strands of blond hair were coiled around its bristles.

The hair sample was packaged and delivered to a lab in Washington, D.C., for neutron activation testing on Dec. 10, 1971. The report, signed by C. Michael Hoffman, acting chief, forensic staff, division of Alcohol, Tobacco and Firearms, came back a month later.

Guzzi folded the report, slipped it into an envelope and drove 30 miles to deliver it by hand to the Middlesex County Prosecutor's Office in New Brunswick.

When he arrived, Guzzi gave the lab results to C. Judd Hamlin, a former public defender who had been named first assistant prosecutor the previous spring. Hamlin oversaw a busy office of 35 prosecutors, and that year he was juggling 21 murder cases and 4,000 indictments.

In the Balabanow case, Hamlin wanted corroborating evidence. Hair analyses in the early 1970s were considered reliable enough to exclude suspects but not to convict them.

Until investigators in his office could find an eyewitness, an accomplice or additional forensic evidence, Hamlin wouldn't consider a murder charge against Zarinsky.

"We'll take a look at it" was the only guarantee he would give the cop from the next county.

Two years went by. During that time, Guzzi, now a captain, checked in periodically with the detectives assigned to the Balabanow case. Each time, he was told the same thing: "We're working on it."

Meanwhile, Agnes Calandriello, her hair grayer and her face gaunt from years of not knowing what happened to her daughter, called Guzzi every day.

He did not know what to say anymore. What could he say?

"Agnes, we're working on it."

'MATTER OF TIME'

Guzzi was positive Zarinsky would strike again. But where? When?

In his file was a report from a psychiatrist who had examined Zarinsky in 1963: "We do not believe schizophrenics ever recover. Sometimes they go into periods of remission. However there is always the problem of recurrence of the psychotic symptoms and abnormal behavior. Remission may be short or lengthy."

"He will kill again," Guzzi would tell his fellow cops. "It's only a matter of time."

Then, on Dec. 13, 1974, two teenage girls went missing in Woodbridge in Middlesex County, the township where Linda Balabanow's body had been found, five miles from where Zarinsky lived with his parents and wife.

Joanne Delardo

Joanne Delardo and Doreen Carlucci were last seen on that Friday night, 12 days before Christmas, on their way from a dance at a Catholic youth center.
A witness saw the girls walking along a busy avenue around 10 p.m. They had come from a neighborhood dairy store and were eating ice cream cones and chattering away.

John Delardo had dropped off his 15-year-old daughter and her 14-year-old friend at the dance. He was supposed to pick them up, but he went home and fell asleep on the couch, and the girls never called for a ride.

At midnight, Delardo's wife, Jeanette, woke him up.

"Joanne's not home yet," she said.

Delardo got in the car and drove all over town looking for the girls. Maybe they had gotten a ride with friends and forgotten the time. Maybe they had met up with Joanne's brother, Johnny, and gone to a late movie. The girls were always saying they were bored -- there was nothing to do in Woodbridge.

At 4:55 a.m., the Delardos and the Carluccis reported their children missing. The rest of that weekend, scores of neighbors and other volunteers joined the search. A reward was offered for information leading to their safe return.

Two weeks later, on Dec. 27, a cyclist discovered the girls' bodies along a remote country lane 30 miles away, in Manalapan Township in Monmouth County.

They had been badly beaten around the head and shoulders. Delardo's body was naked from the waist down, just as Linda Balabanow's had been. Carlucci's body was almost entirely nude. Yet police told their families there was no evidence of sexual assault on either girl. Both had been strangled, and, like Balabanow, the Delardo girl still had black electrical cord knotted around her neck.

"Zarinsky," Guzzi thought when he heard. Maybe now, someone would listen to reason.

SOURCE NOTES

All scenes described in this series are based on official documents, contemporary published accounts and interviews. Direct quotations are taken from court records, police reports or from interviews with the people who spoke the words.

Given the passage of time, extra efforts were made to confirm quotations with the people to whom they are attributed. Where possible, quotations were cross-checked with others who may have heard them. Where the source or recollection of a quotation was imprecise, the words were paraphrased or omitted.

Details of the scene in the State Police classroom are taken from notes kept by Sam Guzzi in November 1971 and from dozens of interviews with Guzzi between August 2006 and August 2007.

Details of the scene in Linda Balabanow's bedroom are taken from Guzzi's investigative notes from November 1971; interviews with Guzzi; and interviews with Alan Balabanow in September and November of 2006.

Details of the lab tests on Balabanow's hair are taken from the forensics report by C. Michael Hoffman dated Jan. 10, 1972.

Details of the scene in which Guzzi delivers the forensics report to Middlesex County, and the account of the workings of the Middlesex County Prosecutor's Office, are taken from Guzzi's investigative notes; interviews with Guzzi; and a July 2007 interview with C. Judd Hamlin, who was first assistant prosecutor at the time.

Details of Zarinsky's mental condition are taken from a 1963 evaluation written by psychiatrist James Spradley.

Details of the 1974 homicides of Joanne Delardo and Doreen Carlucci are taken from interviews with Delardo's parents and sisters n September and October 2006; an Oct. 11, 2006, interview with former Middlesex County first assistant prosecutor William Lamb; articles in The Star-Ledger dated Dec. 17, 1974, Jan. 26, 1975, Feb. 26, 1975, and Aug. 19, 1999; and articles in the New York Times dated Dec. 17, 1974, Dec. 24, 1974, Dec. 28-31, 1974, Jan. 3, 1975, and Jan. 8, 1975.